This invention relates generally to electrostatic precipitators, and more particularly, to methods of improving electrostatic precipitator performance.
Known electrostatic precipitators remove particles from gas and are generally used in industrial applications. At least some known methods of determining electrostatic precipitator performance are based on current density (A/m2). Generally the current density may be determined by measuring the electrons bridging a gap between emitting electrodes and sets of collecting electrodes. Electrode operating voltage may be variable because of the buildup of dust or contaminant particles on the collecting plates or the emitting electrodes.
Known emitting electrodes have an associated electric field, are positioned at least at the precipitator input and output, and may be designed to generate the most possible current for any given situation. The electric fields of properly functioning discharge electrodes located at the precipitator inlet may capture significantly more contaminant particles than electric fields of properly functioning discharge electrodes located at the precipitator outlet. As such, electric fields at the inlet may need to overcome a space charge caused by a huge number of particles collected between the emitting and collecting electrodes. Generally, electric fields at the outlet may be subjected to significantly fewer particles, so electrons migrate much easier. Because it is easier to have high current densities in an electric field at the precipitator output than in an electric field at the precipitator input, it may be difficult to impart power to an electric field at the input and it may be easier to impart excessive power to an electric field at the output.
Electrostatic precipitators may not fully use their power supplies. For example, mismatched impedance may prevent the power supply from reaching secondary design limits. This may result in operating voltages of about 10-20% lower than rated voltage, while the input power may be at its operating limit. The opposite may also occur. Should the sparking rate remain the same, minimally increasing or decreasing the system impedance may increase the total wattage input to the electric field, which may improve overall precipitator performance.
Known discharge electrodes are generally not designed to match the impedance of their associated electric fields. Rather, they are generally designed to facilitate maximizing the power in their associated electric fields. Measuring and optimizing watts may provide the best impedance matching.